This proposal is a competing renewal for the Penn Center for AIDS Research (CFAR), which includes the University of Pennsylvania, The Children's Hospital of Philadelphia and The Wistar Institute. This CFAR links faculty engaged in HIV/AIDS research at these institutions and is committed to goals laid out in the NIH CFAR mission statement and fostering interdisciplinary HIV/AIDS research activities on campus. The CFAR's Specific Aims are to: 1) provide leadership that creates and supports infrastructure for innovative, interdisciplinary, collaborative, and translational HIV/AIDS research on the CFAR campus;2) create, sponsor, and facilitate educational and training efforts that span scientifically diverse HIV/AIDS areas;3) conduct and coordinate community outreach efforts that communicate knowledge to and solicit input from domestic populations, particularly those hardest to reach and hardest hit by the HIV/AIDS epidemic in the Philadelphia area;4) develop partnerships with institutions and investigators outside the U.S. that strengthen the capacity for HIV/AIDS research, education, and training in developing countries most affected by the AIDS pandemic;and 5) promote collaborative research programs between CFARs that enhance and extend the added value that individual CFARs provide to the national CFAR network. The Penn CFAR includes four Scientific Programs: Virology/Pathogenesis, Clinical/Therapeutics, Immunology/Vaccine, and Behavioral &Social Sciences. The Center is directed by Dr. James A. Hoxie and co-directed by Dr. Ronald Collman and governed by an Executive Committee with input from an Internal Advisory Board and External Advisory Committee. The CFAR has a Developmental Core and seven Shared Resource Cores that provide key services to CFAR investigators not available elsewhere on campus including Clinical, Viral/Molecular, Immunology, Behavioral &Social Sciences, Biostatistics &Data Management, Non-Human Primate, and International. The Center remains committed to developing a creative, comprehensive, and interdisciplinary AIDS research program that is fully integrated with the research and educational mission of the University and dedicated to meeting the challenges of the AIDS pandemic.